


Galaxy Brain Jigen

by thisislegit



Category: Lupin III
Genre: Comedy, Memes, Multi, OT4, this started on discord i wanted to share
Language: English
Status: Completed
Published: 2019-12-30
Updated: 2020-08-05
Packaged: 2021-02-27 14:21:46
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 4
Words: 3,548
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/22028497
Author URL: https://archiveofourown.org/users/thisislegit/pseuds/thisislegit
Summary: Jigen makes some revelations Lupin and Fujiko are not willing to accept. Goemon gives his support.Chapters 1,2, and 4 are GEN Rating. 3rd chapter is 18+
Relationships: Ishikawa Goemon XIII/Jigen Daisuke/Arsène Lupin III/Mine Fujiko
Comments: 22
Kudos: 149





	1. Testing Boundaries

Jigen was lying on the couch while Fujiko and Lupin muttered to themselves at the table over blueprints. Tipping his hat back, he blinked at the ceiling and asked, "You ever think about how cereal is soup?"

Lupin already knew where this was going, used to conversations like this early in their partnership as he replied, "Please don't do this."

Fujiko rubbed her temples, "It's not a soup."

"What exactly are the parameters that make something a soup."

"You don't eat cold soup!"

"Gazpacho," Jigen replied.

Goemon opened one eye, "Wouldn't that make smoothies a soup?"

"I'm begging you," Lupin clasped his hands together, "not to encourage him."

"No, let the man speak." Jigen was sitting more attentively now.

"You drink smoothies! You don't drink soup!" Fujiko swiveled around in her chair about ready to pull her hair out.

"Technically you do drink soup. People sometimes put it in a thermos where a spoon isn't necessary, and even then." Jigen smirked.

"What about the chunks in it?" Lupin then covered his mouth with both hands, "Oh my god, cereal is a soup."

"HA!"

* * *

Lupin almost had the lock on the safe open when his ear bud buzzed.

Jigen's voice came from the other end, "Hey, I got another revelation for ya."

"I'm in the middle of breaking open this safe. I'm not going to entertain you this time." He refused to take the bait.

"Hot dogs are sandwiches."

"Hot dogs are not sandwiches!" Lupin took the bait.

"Is a hot dog not meat and toppings slapped between two pieces of bread."

Fujiko's voice came over the com next, "It's one piece of bread. It's not cut all the way through. It's not a sandwich."

"So, we're just gonna pretend the bread used for hoagies are always cut all the way through? I think not. We both know better."

"We as a society have to draw the line somewhere, _Jigen_ ," Lupin hissed.

Goemon's question came very quietly, "So quesadillas are sandwiches?"

"SHUT UP." Fujiko and Lupin shouted. Lupin had popped open the safe and switched out the real item for the fake at this point.

"Once again our local samurai is making all the right assumptions."

"Technically a hot dog is a sandwich," Zenigata's voice came from behind Lupin as he was about to enter the floor grate.

"Hear that. For the first time in my life, the law's on my side."

"I'm so snatching the treasure from you all after we get out of here," Fujiko sighed.

* * *

Lupin pulled the blanket up to his chest, with one arm around Fujiko, and the other around Jigen. He was closing his eyes when he heard the last thing he wanted to hear.

Jigen had placed a hand on his bare chest, "So you're gonna hate me for this."

"Jigen. We just had sex. Can we go to bed without another argument."

"Hardly an argument if I keep winning with Goemon's support."

Goemon muttered, "Is that what I'm doing?"

"Jigen, I've had enough. I just want to sleep." Fujiko glared at him from over her shoulder.

"All right fine." It was quiet for a few blissful moments until Jigen said, "Lasagna is cake."

"UGH."

Fujiko sat up in bed," IT'S NOT CAKE. CAKE IS SWEET. YOU CAN'T JUST CALL WHATEVER YOU WANT CAKE."

"It's layered! It has the grains, pasta instead of bread, the glue that holds it together, sauce instead of frosting, and a festive topping, cheese instead of sprinkles. That's cake. It's spaghetti cake." Jigen had sat up as well, his hand still planted on Lupin's chest.

Lupin felt a headache coming on, "You know what fuck it. Just fuck it. Lasagna is cake. I don't care anymore. _Can we please just go to sleep._ "

"Ah." Goemon said.

Jigen looked behind him, "What?"

"That means seven layer dip is a parfait."

"Goemon," Jigen paused and then grinned, "I could kiss you right now. Why didn't I think of that."

"You son of a bitch, you turn on that light. I'm getting my dictionary. We are settling this right now." Fujiko pointed an angry finger at the other two.

Lupin groaned as he sunk himself further under the blankets.


	2. "Beans Beans The Wonderful Fruit" Makes Sense Now

Lupin and Goemon were walking back to their hideout with coffee in tow. Whereas Lupin himself had been bundled up with every warm article of clothing he could squeeze into, Goemon settled for something lighter with only a coat and a scarf adorning his neck. The atmosphere outside was about as cold and icy as it was in the wide apartment he’d rented for the occasion, so the thief decided he could do a quick run before breakfast.

“Thanks again for coming with me, Goemon.”

“I did not wish to be present for the blood bath that was to occur after your absence.”

Lupin shuddered at the thought. “He’s doing it on purpose. We used to have conversations like that when we first started out as partners, but he toned it down. Now that he knows it pisses her off, he won’t stop.”

“I’m aware.”

“Then why are you helping him?”

Goemon had the decency to blush as he said, “It was not my intention to upset her. I simply thought they were interesting ways of viewing things.”

“I can’t tell if that’s stupid or cute, so I’m gonna go with both.”

When he opened the door to their apartment, it was eerily quiet. Goemon scanned the area for bullet holes as he took off his shoes, and Lupin looked for bloodstains. Seeing as how neither were visible in the main room, they nodded to each other and finished getting out of their outerwear. The curtains were all closed, but the light in the dining room was on.

“We’re back.” Lupin called out.

No response.

“What if they poisoned each other’s drinks?” Goemon asked.

“Wouldn’t be the first time.”

The swordsman’s eyes widened at this, but Lupin waved him off saying, “It was just a joke.”

The two entered the dining room and saw Fujiko daintily eating from her plate of pancakes. Jigen was sitting opposite to her pouring too much syrup over his own. Two untouched plates sat along the other two sides of the table, one that matched Jigen and Fujiko’s while the other held a different fair of an egg over rice with soy sauce and pickled vegetables.

“You’re eating dessert for breakfast, again.” Goemon set Jigen’s coffee in front of him.

“Pancakes are not dessert. They’re a breakfast staple,” Jigen said.

“Fujiko~. I have your soy vanilla latte,” Lupin set it down with a flourish. “No whipped cream.”

“Thank you, Lupin. You’re a life saver.”

Lupin put his jacket over his chair before sitting down as he listened to the clinking of silverware on plates. Normally, he was uncomfortable when they were all this quiet. However, after the past two days he was thankful for the silence.

“Huh,” Jigen said.

Oh no.

He knew that tone. That was the contemplative yet curious realization tone. Fujiko was already glaring at Jigen over the table with a forkful of pancake half raised to her lips.

“If you think about it-”

“No. Don’t do this Jigen. We’ve had enough!” Lupin slapped his hand down onto the table. “You’re upsetting, Fujiko.”

“If you finish that sentence, I will leave for six months.” Fujiko’s tone was severe. She meant business.

Jigen slowly set his fork down. He gave Fujiko a long look, and then gave Lupin the same treatment. Another moment passed, and he took off his hat to gently set it onto the table. Lacing his fingers together, he placed his open palms onto his stomach and leaned back in his seat, giving them both his full attention. “Soy.”

“Jigen!” Lupin was almost out of his seat.

“Vanilla.”

“Don’t!”

“Lattes.”

“I swear to god!”

“Are a type of three bean soup,” he finished with a smirk.

Fujiko stood up from her seat, “I’m leaving.”

“Fujiko, wait!”

“Actually Jigen,” Goemon chimed in.

All three of them turned to the samurai, curiosity clear in their expressions.

“Coffee beans aren’t beans. They’re seeds. The name comes from the appearance association, but they come from a type of cherry or stone fruit.”

“Well I’ll be damned,” Jigen said.

Fujiko took her seat back at the table, and Lupin watched with relief as the group went back to eating. He was going to give Goemon the biggest thank you after breakfast. Jigen made sausage links and Lupin was wrapping a couple of them into his pancakes when he saw the gunman slap his leg.

“Fried rice is a salad.”

Fujiko screamed.


	3. The Pizza Debacle

Lupin was a very happy customer as he sat in the uncomfortable dining room chair. Jigen pressed the head of Lupin’s cock against his lips before taking the tip into his mouth with a huff. He gave the rest a few short strokes with his palm making Lupin moan and curl his fingers into fluffy hair. Jigen’s hat had been set aside sometime while they were kissing, but having him on his knees was equally satisfying to Lupin following a two week dry spell.

It wasn’t as though they didn’t have time. They had time, but when one of them was in the mood the other seemed to be busy. It resulted in a rather frustrating back and forth which fostered an irritation so high strung that even Goemon was getting annoyed watching them, hence his sudden run to the market or where ever before things spiraled into current events.

Jigen moved one of Lupin’s legs over his shoulder so he had more space to start fondling his balls, but cold fingers made Lupin gasp and grab onto the edge of his seat. He was going to start thrusting when Jigen pulled off to just stroke him with his palm.

“Lupin.”

“Mmph, yeah?”

“You ever think about how many ways we just remade pizza?”

“Why are you even thinking about that? What would possibly make you think about that when my dick is in your mouth?”

Jigen continued his stroking sending threads of pleasure up Lupin’s stomach, but he was torn between being horny and offended as Jigen just trapped him under the guise of a blowjob only to have another of his “revelations”. Did he even want the blowjob anymore? Jigen dragged his tongue along the length of Lupin’s cock and he decided he could tolerate it for a little longer.

“I was just thinking about dinner, then I thought about mozzarella sticks cause they’re both phallic, but then I realized it’s just pizza with more steps.”

“Oh _my god_.” It was a mix of indignation at the conversation they were having and a reaction to Jigen giving the head of his cock a hard suck when he finished his sentence.

“I know I called lasagna a spaghetti cake, cause it’s true, but it’s really pizza too.”

Lupin had no idea how he thought this was appropriate blowjob talk, but Jigen was pushing a hand under his shirt to roll a nipple between a thumb and forefinger whilst taking Lupin into his mouth again. If only it could stay like this. Peacefully quiet and pleasurable, but then Jigen was pulling off to keep the desperately unwanted conversation going.

“Meatball subs? Pizza.” He gave Lupin’s balls a few licks before returning his attention to the shaft. “Quesadillas when you dip them in salsa? Pizza.”

“God I just want you to do everything _but_ speak.”

Jigen let the head of Lupin’s cock slip back between his lips and poke on the inside of his cheek, “Ahn ya know wha?”

“ _Don’t talk with your mouth full_.”

The kiss he received on the head of his dick was patronizing, and did Lupin really want this blowjob? Did he? Was it worth the emotional turmoil?

“The idea that adding tomato sauce and cheese to something turns it into a pizza means infinite possibilities.”

“Yeah, pizza toast is a thing and- wait. NO. YOU’RE NOT PULLING ME INTO YOUR BULLSHIT. PUT MY DICK BACK IN YOUR MOUTH RIGHT NOW.”

“What is going on in here?” Goemon stood in the doorway holding a paper bag of groceries in one arm and a few plastic bags in the other.

Jigen was still stroking Lupin’s cock at a faster rhythm as he said, “Goemon. Just the man I wanted to see. I need your opinion on something.”

“NO HE DOESN’T.”

Goemon gave them a once over and asked, “Is it about Lupin’s penis?”

“No, this is fine.”

“NO IT’S NO-ah~.”

Jigen pressed the wide flat of his tongue along the curve where the head met the shaft before taking him back into his mouth with an audible suck that had Lupin curling forward. He hated how close he was, and he gripped one hand in Jigen’s hair while the other dug fingers into Jigen’s shoulder. The stroking on his spit covered cock increased in pace, and when Jigen wiggled his tongue into the slit Lupin was cumming in his mouth with a drawn out moan. Gasping, his arms went limp but the annoyance remained and would rise to the surface like an uninhibited fury once Jigen stopped swallowing around his dick.

He wasn’t sure if it was mercy or torture when Jigen pulled his mouth off to say, “Adding cheese and tomato sauce to something would turn it into a pizza, yeah?”

Goemon having watched the display with a neutral look on his face narrowed his eyes at the comment. “Then where do we draw the line between a pizza and a sandwich.”

“That’s what I was thinking!” Jigen tucked Lupin back into his pants. “We need to make a chart.”

“Before we get out the papers could I also receive a blowjob?”

“Yeah, I got time.”

At this point, Lupin hid his face into his hands. “I want a divorce.”

**Notes for the Chapter:**

> Changed Dialogue
> 
> “Why are you even thinking about that? What would possibly make you think about that when my dick is in your mouth?”
> 
> Jigen shrugged while moving his hand at a steady pace, "Lupin's dick, mozzarella stick. They rhymed while I was thinking of dinner plans."


	4. The Cube Rule

**Notes for the Chapter:**

> thank you peachy_keener for the inspiration with your comment :3c
> 
> this is very rushed, un-betad and my big gay hands had to put it down as soon as possible before i lost motivation

Lupin was having a good evening. He was waiting on Fujiko to come over for their midnight rendezvous, but in the meantime he was cuddled up next to Jigen on the dinky couch watching some noir movie he wasn’t actually interested in. Jigen, on the other hand, was very interested in it as he’d provided scathing commentary whenever something ridiculous happened only to get a peck on the cheek or the chin for his troubles.

Thankfully, it’d been quiet the past few months. Fujiko and Jigen were getting along without those stupid food comments, and Goemon was joining in more with their group intimacy outside of the bedroom. Yes, all was well except for the growing noise of rushed tapping heading towards the living room.

Goemon opened the door more hurriedly than usual, and his eyes zoned in on the two. Did something happen? Was there someone outside? Was it Zenigata? Lupin sat up and opened his mouth to say something, but Goemon cut him off by holding up a hand.

Goemon said, “Jigen, I’ve realized something.”

“Hm?” Jigen leaned his head back onto the couch.

“A hot dog is not a sandwich.”

“No,” Lupin muttered.

Jigen narrowed his eye, “What do you mean?”

“No!” Lupin wasn’t about to go through this again.

“Jigen, it’s a taco.”

“Oh my god.” Jigen grinned. “Goemon! Holy shit, Goemon.”

“NO NO NO. ENOUGH. I’VE HAD ENOUGH.”

Both Jigen and Goemon stopped talking both from the tone and the volume.

“This isn’t funny anymore! I don’t care! I don’t want to hear about it! A couple of jokes was well and good, but this is the last straw!”

“I just thought-.”

“I DON’T CARE WHAT YOU THINK.” Lupin cut Goemon off, but paused when he saw Goemon’s expression harden for a moment.

“My apologies for the intrusion.” Goemon switched back to a more formal speech and walked out.

Sighing, Lupin sank back into his spot only for his head to meet the sofa instead of Jigen’s side. He turned his head up to see Jigen had scooted over and looked as though he was preparing to stand up. Lupin didn’t have to hear the words to know what Jigen was thinking. They made eye contact for a brief moment where Jigen shook his head before he followed after Goemon.

This wasn’t fair. Jigen was being a dick to Fujiko first with the stupid food revelations. Sure they were harmless, but what happened to no being a deterrent? Laying on his side, he thought back to the times the topic came up, and how Goemon and Jigen seemed to connect on something so stupid and pointless as food classification.

_Lupin shuddered at the thought. “He’s doing it on purpose. We used to have conversations like that when we first started out as partners, but he toned it down. Now that he knows it pisses her off, he won’t stop.”_

_“I’m aware.”_

_“Then why are you helping him?”_

_Goemon had the decency to blush as he said, “It was not my intention to upset her. I simply thought they were interesting ways of viewing things.”_

Lupin groaned and rolled to lay on his face. Why the hell was he letting himself get mad about this? There were worse topics to talk about, and they were having fun. Shouldn’t that matter more than his annoyance based on minor disagreements which had no real life consequences? It’s not like he forgot when he did the same thing with Jigen when it was just them and they were much younger. It was something to laugh at. Sometimes they’d even mix up languages to make new words that equaled the meaning but were funny to say.

He didn’t know what was worse. The fact that he was sitting here moping before his night with Fujiko, or the fact that he was having a falling out with two of his partners _over food terminology_.

So what if a hot dog was a taco? At least it wasn’t a sandwich. When his eyes met the TV again the credits were rolling, which is fine because he was sure there was like ten minutes left of that movie anyway. Getting up, he looked around the small townhouse until he found Jigen and Goemon sitting on the balcony on the second floor.

The conversation stopped when he opened the sliding doors, and Jigen blew out a few puffs of smoke from his cigarette while Goemon stared at the blacked out sky. Light pollution really sucked in this town.

“Goemon, I’m sorry.”

“It is fine. I have no issue with changing the topic if it is something you do not want to hear discussed.”

Wow, he was hitting Lupin with the hard formal phrasing. There was only one way to repair this bridge, which involved him swallowing his pride and not getting laid tonight.

“Are you two basing it on the food’s shape or by ingredients?”

Jigen blinked up at him, “Depends on the food.”

“It’d be easier if you used the cube rule.”

“…what is the cube rule?” Goemon asked.

When Fujiko walked into the townhouse, she knew she was stunning. Her deep blue dress accentuated some of her best features and made the new auburn highlights in her hair come out warm. What she hadn’t expected was the sight of three grown men in varied states of distress as they took turns pointing at a whiteboard chart that read “The Cube Rule of Food”.

It actually took her a moment to even register the conversation. Goemon stood with his hair in a ponytail and his shirt half off as he drew on said whiteboard talking about the different types of sushi and which varied between a burrito or what could be considered toast. Jigen with his hair out of his face and his sleeves rolled up stood practically hunched over Lupin to say something along the lines of “burritos are closed on both ends so wouldn’t that classify as a calzone?”. Lupin was wearing his glasses, his sleeves also rolled up as he flipped between a cookbook and what appeared to be physics dictionary. What in the hell had she walked into?

“Hello?” Fujiko said and all three men turned to look at her. “I have a date tonight. What’s going on.”

“Fujiko! Just give me a second to get dressed,” Lupin placed his hands on the desk which sent a few books scattering to the wayside.

“No. Explain.”

Goemon chose that moment to say, “We were discussing food classification based on shape instead of ingredients. This makes ramen a type of salad.”

She stared at the earnest expression on Goemon’s face, then glanced at the other bastard men she considered her partners. Jigen gave her a sly grin, while Lupin gave her a softer one and shrugged. Okay. Change of plans. Her heels clicked on the wooden floor, and she took the marker out of Goemon’s hand.

“If ramen is a salad, that means cereal is a salad, not a soup.” She added that onto the notes. “That also makes the question soup or salad irrelevant.”

“What’s a super salad?” Jigen asked, the smile not leaving his face.

Goemon covered his mouth to hide his laughter, and Fujiko rolled her eyes. Lupin could make it up to her later which a much more expensive date than the deep dish pizza, now classified as a type of quiche, they would order in a little while.

**Author's Note:**

> are uncrustables not just one step removed from being ravioli?


End file.
